Method of winding toroids and toroids produced thereby



March 29. 1966 COLLINS I 3,243,750

METHOD OF WINDING TOROIDS AND TOROIDS PRODUCED THEREBY Filed March 2. 1961 F1 0 2 fii a LLLLLLL /0 FAQ 5. 2-4500 52 70/ 2 15 70 5'5 INVENTOR. GFQV L. COLL/IVS By jwrvm United States Patent 3,243,750 METHOD OF WINDING TOROIDS AND TOROIDS PRODUCED THEREBY Gary L. Collins, Downey, Calif., assignor to G. L. Collins Corp., Long Beach, Calif., a corporation of California Filed Mar. 2, 1961, Ser. No. 92,970 2 Claims. (Cl. 336-150) The present invention relates to the coil winding art and has particular usefulness in the manufacture of a tapped toroidal coil wherein it is desired that each section of the winding between taps thereon have and provide substantially identical electrical and magnetic properties.

In the manufacture of certain tapped coils such as, for example, a tapped coil wound on a toroidal-shaped core structure, it is desirable that each section between taps have the same electrical resistance, the same electrostatic capacitance, and produce substantially the same magnetic eflect in the core when a current traverses the winding so that the tapped coil may be used as, for example, a potential divider dividing the potential applied thereto evenly between taps or, for example, as an in ductance unit wherein the inductance measured between different taps is substantially the same.

The present invention has as one of its objects the provision of new means and techniques whereby these indicated desirable results are accomplished in a simple, inexpensive manner which when practiced assures obtainance of these results.

Briefly, as exemplified herein, a plurality of wires are first mounted in side-by-side relationship on a flexible strip of insulating material; the strip is then wound around the core, after which opposite ends of adjacent wires are interconnected at junction points defining the taps of the coil.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. This invention itself, both as to its organization and manner of operation, together with further objects and advantages thereof, may be best understood by reference to the following description taken in connection with the accompanying drawings in which:

FIGURE 1 is a perspective view illustrating a toroidal coil structure during one stage in its manufacture and shows a portion of the winding broken away to show the toroidal core.

FIGURE 2 illustrates a portion of the wire-mounting flexible strip which is wound around the core.

FIGURES 3 and 4 illustrate the manner in which opposite ends of adjacent wires in FIGURES 1 and 2 are interconnected.

FIGURE 5 illustrates a portion of the finished structure.

Referring to the drawings, the structure appears to be best described by the manner in which it is fabricated.

Initially a plurality of nine-enamel-covered wires 1-9 are mounted or afiixed to an elongated strip of insulating material as, for example, of pressure-sensitive Mylar, by gluing or by direct bonding with the enamelcovered wires 1-9 using heat and/or pressure in the process, the wires being insulated from each other by their enamel coating.

The strip 10 with the wires thus afi'ixed thereto is wound around the toroidal core 11 which is illustrated as being generally square in cross section, the result being that the wires are wound simultaneously as a group with the 3,243,750 Patented Mar. 29, 1966 ice spacing between wires corresponding to the same turn being always of the same equal spacing. The strip 10 may be wound either such that opposite sides thereof abut or are spaced from each other or overlap somewhat and, of course, the strip 10 may be wound either as a single layer on the core 11 or in multilayers.

It will thus be seen that a single winding of tape 10 results in winding of a plurality of coils as illustrated in FIGURE 3 wherein the coil 21 corresponds to wound Wire 1, coil 22 corresponds to wire 2 and coil 23 corresponds to wire 3. For convenience of reference and explanation, adjacent ends of the wires on the starting end of strip 10, i.e. that end of strip 10 which is first wound on the core, are characterized by the letter S, denoting start; and the other ends of the same wires are characterized by the letter B, denoting end.

The starting end 18 of wire 1 constitutes one end of the finished winding and is designated also as lead 31. The ending end 1E of wire 1 and the starting end 28 of wire 2 are interconnected and define a first tap to which lead 32 is connected, the same being, for example, an extension of either wire end IE or wire end 28. Likewise, the ending wire end 2E is connected to the starting wire end 38 to define a second tap to which the lead wire 33 is connected. In like manner the other starting and ending ends of the other wires are interconnected to provide taps which are connected to corresponding leads 34, 35, 36, 37, 38 and 39. The tenth lead 40 corresponds to the wire end 9B.

These various leads 31-40, also being enamel-covered wire for insulation purposes, may be uniformly spaced and secured around the outer periphery of the assembly by insulating tape 45 wound so that successive ones of such leads extend through small openings between adjacent turns of the finishing and securing tape 45.

While the particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. In the method of forming a tapped coil of wire on a ring-shaped core, the steps including mounting a plurality of wires on an elongated narrow flexible strip of nonmagnetic insulating material with such wires being spaced from each other and extending generally parallel to each other and longitudinally of said strip, said strip being much narrower than the circumference of said ringshaped core, spirally winding said strip with said Wires thereon generally radially around said ring-shaped core with said wires between said strip and said ring-shaped core such that adjacent turns of said strip are spaced circumferentially around said core with said strip covering said wires, and interconnecting individual different ends of different ones of said wires in a series circuit such that each wire produces an additive magnetic field in said ring-shaped core when current flows in said series circuit.

2. A tapped coil on a ring-shaped core, including a ring-shaped core, a narrow elongated strip of nonmagnetic insulating material, a plurality of parallel extending wires mounted longitudinally on and under said strip, said strip being much narrower than the circumference of said ring-shaped core and being spirally disposed around said core such that adjacent turns of said strip are spaced circumferentially around said core member, and in- 3 4- dividual different ends of difierent ones of said wires be- 1,133,466 3/1915 Baeumler 336-150 ing interconnected in .a series circuit such that each Wire 1,586,889 6/1926 Elmen 29?...15557 produces an additive magnetic field in said ring-shaped 2,961,747 11/1960 Lyman 29-155.57 core member when current flows through said series cir- 2,988,804 6/ 1961 Tibbetts 29155.57

cuit. 5

JOHN F. CAMPBELL, Primary Examiner.

References Cited by the Examiner MELTON HERSHFIELD Examiner UNITED STATES PATENTS A. W. LEWIS, J. W. BOCK, Assistant Examiners. 890,988 v6/1908 Kitsee 29 455.57 1,127,921 2/1915 Pickhard s 336-4150 

1. IN THE METHOD OF FORMING A TAPPED COIL OF WIRE ON A RING-SHAPED CORE, THE STEPS INCLUDING MOUNTING A PLURALITY OF WIRES ON AN ELONGATED NARRROW FLEXIBLE STRIP OF NONMAGNETIC INSULATING MATERIAL WITH SUCH WIRES BEING SPACED FROM EACH OTHER AND EXTENDING GENERALLY PARALLEL TO EACH OTHER AND LONGITUDINALLY OF SAID STRIP SAID STRIP BEING MUCH NARROWER THAN THE CIRCUMFERENCE OF SAID RINGSHAPED CORE, SPIRALLY WINDING SAID STRIP WITH SAID WIRES THEREON GENERALLY RADIALLY AROUND SAID RING-SHAPED CORE WITH SAID WIRES BETWEEN SAID STRIP AND SAID RING-SHAPED CORE SUCH THAT ADJACENT TURNS ON SAID STRIP ARE SPACED CIRCUMFERENTIALLY AROUND SAID CORE SAID STRIP COVERING SAID WIRES, AND INTERCONNECTING INDIVIDUAL DIFFERENT ENDS OF DIFFERENT ONES OF SAID WIRES IN A SERIES CIRCUIT SUCH THAT EACH WIRE PRODUCES AN ADDITIVE MAGNETIC FIELD IN SAID RING-SHAPED CORE WHEN CURRENT FLOWS IN SAID SERIES CIRCUIT.
 2. A TAPPED COIL ON A RING-SHAPED CORE, INCLUDING A RING-SHAPED CORE, A NARROW ELONGATED STRIP OF NONMAGNETIC INSULATING MATERIAL, A PLURALITY OF PARALLEL EXTENDING WIRES MOUNTED LONGITUDINALLY ON AND UNDER SAID STRIP, SAID STRIP BEING MUCH NARROWER THAN THE CIRCUMFERENCE OF SAID RING-SHAPED CORE AND BEING SPIRALLY DISPOSED AROUND SAID CORE SUCH THAT ADJACENT TURNS OF SAID STRIP ARE SPACED CIRCUMFERENTIALLY AROUND SAID CORE MEMBER, AND INDIVIDUAL DIFFERENT ENDS OF DIFFERENT ONES OF SAID WIRES BEING INTERCONNECTED IN A SERIES CIRCUIT SUCH THAT EACH WIRE PRODUCES AN ADDITIVE MAGNETIC FIELD IN SAID RING-SHAPED CORE MEMBER WHEN CURRENT FLOWS THROUGH SAID SERIES CIRCUIT. 